1. Field of the Invention
The present invention relates to isolated nucleic acid sequences encoding polypeptides having tripeptide aminopeptidase activity. The invention also relates to nucleic acid constructs, vectors, and host cells comprising the nucleic acid sequences as well as recombinant methods for producing the polypeptides.
2. Description of the Related Art
Tripeptide aminopeptidases (EC 3.4.11.4) are exopeptidases which catalyze the removal of unsubstituted tripeptides from the N-terminus of peptides, oligopeptides or proteins. Tripeptide aminopeptidases may be unspecific in cleaving any tripeptide sequence from the N-terminal end, or specific in cleaving specific types of tripeptide sequences.
The isolation of microbial genes encoding tripeptide aminopeptidases have been reported previously. For instance, Butler et al. disclose the cloning and expression of a Streptomyces lividans tripeptide aminopeptidase gene (1995, Applied and Environmental Microbiology 61:3145-3150). Mierau et al. disclose the cloning and expression of a Lactococcus lactis tripeptide aminopeptidase gene (1994, Journal of Bacteriology 176: 2854-2861).
It is an object of the present invention to provide isolated nucleic acid sequences encoding polypeptides have tripeptide aminopeptidase activity.